Addition du chlorure de nitrosyle et de l'oxyde d'azote(III) sur l'allyltriméthylsilane et sur l'allylbenzyldiméthylsilane

Abstract

Le sens de l'addition du chlorure de nitrosyle sur ces composCs organosiliciCs se ddduit de l'effet inductif rdpulsif du groupement trialkylsilyle [6] [7] et de la stabilitd plus grande du carbocation secondaire (rbgle de Markowaikoff). On peut donc attribuer au nitrosochlorure la formule (R1R2R3) Si-CHz-CHCl-CH2NO.La structure des pseudonitrosites obtenus peut Ctre dCrivCe de deux manihes selon que I'on considkre un rri6canisme ionique ou un mCcanisme radicalaire. Si nous appliquons le m6canisme ionique proposC par Levy & Scaq8 [8] l'attaque par le cation nitronium peut conduue aux carbocations I ou I1 :I, carbocation secondaire, se formera de pr6fCrence et l'attaque de l'anion hyponitrite monomhe NO-donnera naissance au pseudonitrosite (R1R2R3) Si-CH2--CH(NO)-CHzN02.

Ultrasonic Nitration of Allylsilanes by Use of Sodium Nitrite and Ceric Ammonium Nitrate

“…Many methods can be used to convert olefins or nitroalkanes to nitro olefins. − Nevertheless, we found that none of those was applicable to synthesis of 1-nitro-3-(triisopropylsilyl)-1-propene with success, except the procedure developed by Jolibois et al Scheme shows our results, in which allyltriisopropylsilane was allowed to react with nitrosyl chloride in chloroform at −60 °C. We then oxidized the resultant nitroso dimer intermediate with m -chloroperbenzoic acid ( m -CPBA) to give the corresponding nitro compound.…”

Preparation of Dinitrogen Trioxide for Organic Synthesis: A Phase Equilibrium Approach

“…68), the product of radical addition (49) was obtained, whereas neither oxime (48) nor nitrosonitrites was formed. The additions to 2,5-dimethoxypropenylbenzene (50), [153] cinnamyl acetate (86), [154] allyltrimethylsilane (51), [155] and many other alkenes [149] exhibits the selectivity of radical mechanism. [156] Generally, a polar reaction (e. g. Eq.…”